Dinosaurs Fell Victim to Perfect Storm of Events, Study Shows

WACO, Texas (July 28, 2014) — Dinosaurs might have survived the asteroid strike that wiped them out if it had taken place slightly earlier or later in history, scientists say.

A new study using up-to-date fossil records and improved analytical tools has helped paleontologists to build a new narrative of the prehistoric creatures’ demise, some 66 million years ago.

The international team of researchers found that in the few million years before an approximately 6 mile wide asteroid struck what is now Mexico, Earth was experiencing environmental upheaval. This included extensive volcanic activity, changing sea levels and varying temperatures. The study is available online.

At this time, the dinosaurs’ food chain was weakened by a lack of diversity among the large plant-eating dinosaurs on which others preyed. This was probably because of changes in the climate and environment. This created a perfect storm in which dinosaurs were vulnerable and unlikely to survive the aftermath of the asteroid strike.

“There have been debates within the scientific community as to the cause of the extinction of dinosaurs. Our study synthesized a huge body of literature on the different explanations,” said Daniel Peppe, Ph.D., assistant professor of geology in Baylor’s College of Arts & Sciences. “Our findings suggest that other factors such as sea level, changes in temperature and lack of species diversity made dinosaurs susceptible to extinction, but were not the cause. The asteroid strike ultimately decimated the dinosaur population and caused their extinction.”

The impact would have caused tsunamis, earthquakes, wildfires, sudden temperature swings and other environmental changes. As food chains collapsed, this would have wiped out the dinosaur kingdom one species after another. The only dinosaurs to survive were those who could fly, which evolved to become the birds of today.

Researchers suggest that if the asteroid had struck a few million years earlier, when the range of dinosaur species was more diverse and food chains were more robust, or later, when new species had time to evolve, then they very likely would have survived.

“The dinosaurs were victims of colossal bad luck. Not only did a giant asteroid strike, but it happened at the worst possible time, when their ecosystems were vulnerable. Our new findings help clarify one of the enduring mysteries of science,” said Steve Brusatte, Ph.D., of the University of Edinburgh’s School of GeoSciences and corresponding author of the study.

An international team of paleontologists and geologists led by the University of Edinburgh studied an updated catalogue of dinosaur fossils, mostly from North America, to create a picture of how dinosaurs changed over the few million years before the asteroid hit. They hope that ongoing studies in Spain and China will aid even better understanding of what occurred.

Their study, published in Biological Reviews, was supported by the U.S. National Science Foundation and the European Commission. It was led by the Universities of Edinburgh and Birmingham in collaboration with the University of Oxford, Imperial College London, Baylor University and University College London. The world’s top dinosaur museums – The Natural History Museum, the Smithsonian Institution, the Royal Ontario Museum, the American Museum of Natural History and the New Mexico Museum of Natural History and Science - also took part.

“Although our research suggests that dinosaur communities were particularly vulnerable at the time the asteroid hit, there is nothing to suggest that dinosaurs were doomed to extinction. Without that asteroid, the dinosaurs would probably still be here, and we very probably would not,” said Richard Butler, Ph.D., of the School of Geography, Earth and Environmental Sciences at the University of Birmingham.

Other contributing authors to the study include: Stephen L. Brusatte of the University of Edinburgh; Richard J. Butler of the University of Birmingham; Paul M. Barrett of the Natural History Museum, London; Matthew T. Carrano of the Smithsonian Institution; David C. Evans of the Royal Ontario Museum; Graeme T. Lloyd of the University of Oxford; Philip D. Mannion of Imperial College London; Mark A. Norell of the American Museum of Natural History; Paul Upchurch of the University College London and Thomas E. Williamson of the New Mexico Museum of Natural History and Science.

ABOUT BAYLOR UNIVERSITY

Baylor University is a private Christian University and a nationally ranked research institution, characterized as having “high research activity” by the Carnegie Foundation for the Advancement of Teaching. The University provides a vibrant campus community for approximately 15,000 students by blending interdisciplinary research with an international reputation for educational excellence and a faculty commitment to teaching and scholarship. Chartered in 1845 by the Republic of Texas through the efforts of Baptist pioneers, Baylor is the oldest continually operating University in Texas. Located in Waco, Baylor welcomes students from all 50 states and more than 80 countries to study a broad range of degrees among its 11 nationally recognized academic divisions. Baylor sponsors 19 varsity athletic teams and is a founding member of the Big 12 Conference.

ABOUT BAYLOR COLLEGE OF ARTS & SCIENCES

The College of Arts and Sciences is Baylor University’s oldest and largest academic division, consisting of 24 academic departments and 13 academic centers and institutes. The more than 5,000 courses taught in the College span topics from art and theatre to religion, philosophy, sociology and the natural sciences. Faculty conduct research around the world, and research on the undergraduate and graduate level is prevalent throughout all disciplines. Visit www.baylor.edu/artsandsciences.